Graphene antidot lattice waveguides

1 Department of Micro- and Nanotechnology, Technical University of Denmark2 Theoretical Nanoelectronics, Department of Micro- and Nanotechnology, Technical University of Denmark3 Department of Physics, Technical University of Denmark4 Theoretical Atomic-scale Physics, Department of Physics, Technical University of Denmark5 Nanointegration, Department of Micro- and Nanotechnology, Technical University of Denmark6 Center for Nanostructured Graphene, Center, Technical University of Denmark7 Aalborg University8 Risø National Laboratory for Sustainable Energy, Technical University of Denmark

DOI:

10.1103/PhysRevB.86.245410

Abstract:

We introduce graphene antidot lattice waveguides: nanostructured graphene where a region of pristine graphene is sandwiched between regions of graphene antidot lattices. The band gaps in the surrounding antidot lattices enable localized states to emerge in the central waveguide region. We model the waveguides via a position-dependent mass term in the Dirac approximation of graphene and arrive at analytical results for the dispersion relation and spinor eigenstates of the localized waveguide modes. To include atomistic details we also use a tight-binding model, which is in excellent agreement with the analytical results. The waveguides resemble graphene nanoribbons, but without the particular properties of ribbons that emerge due to the details of the edge. We show that electrons can be guided through kinks without additional resistance and that transport through the waveguides is robust against structural disorder.